Support device



R. J. LINDEMAN SUPPORT DEVICE Nov. 26, 1968 Filed Aug. 14, 1964 FIG. 4

Inventor Richard J. Li ndemcm United States Patent 3,412,992 SUPPORT DEVICE Richard J. Lindeman, Elmwood Park, Ill., assignor, by mesne assignments, to National Video Corporation, Chicago, 111., a corporation of Illinois Filed Aug. 14, 1964, Ser. No. 389,532 4 Claims. (Cl. 269296) This invention relates to a supporting device particularly useful in the carrying of a glass object which is transported on a conveyor through a heat treating process.

In the manufacture of certain glass objects it may be necessary to pass them through a heating process by means of a conveyor F or example, an annealing furnace for relieving strain in a glass object might require conveyor transport of the object for 100 feet or more. Glass being so annealed is in a semi-fluid state such that its own weight and the irregularities in the conveyor may disturb the object and distort it.

One object especially subject to this problem is the rectangular glass faceplate panel of a color picture tube for a color television receiver. Such a panel is generally of substantial size and weight, e.g., 23 across and pounds in weight, while at the same time it must conform to very precise dimensions for proper functioning in a shadow mask type color tube which is widely used today. Accordingly, annealing of a glass object of this type may involve long distance conveyor travel of a relatively large heavy object in a semi-fluid state, distortions of which must be avoided.

An object of this invention is to uniformly support a glass object on a conveyor in an annealin furnace to minimize distortions thereof due to irregularities in the level of the conveyor and the unsupported weight of the glass itself.

Another object is to provide a simple, inexpensive support for the faceplate panel of a color cathode ray tube during heat treatment thereof.

In a specific form the invention provides a variable support for a glass object to be annealed, such as a picture tube faceplate. A frame member is pivotally mounted about a horizontal axis on a base frame of a ring or hoop configuration. A pair of support posts extend upwardly from the base frame opposite the pivotal mounting of the frame member and another pair of support posts extend upwardly from the frame member on opposite sides of the pivot point thereof. The upper ends of the posts carry pads of steel wool providing support for the faceplate panel thereon. The panel is contacted and supported by the four pads and posts due to the pivotal action of the frame member, despite limited movement of the panel relative to the posts due to irreguarities or dips and bumps in the travel through the annealing furnace when the panel is in a vulnerable state.

In the drawing, FIG. 1 is a perspective representation of the invention in use with an annealing furnace;

FIG. 2 is a side elevational view of the supporting device;

FIG. 3 is an end elevational view of the supporting device; and

FIG. 4 is a bottom view of the supporting device with a faceplate panel carried thereon.

The invention finds particular utility as an annealing crown in manufacture of faceplate panels for a shadow mask type color picture tube. The panel 10, shown in the drawings, is formed of glass of variable thickness with a thin portion being near the center and the thick portion being near the periphery and in the upturned edge flanges thereof. Such a panel may, for example, be in excess of 16 by inches across the major and minor axes thereof and have a weight of 15 or 16 :pounds.

Successful use has been made of commercial sof ice glass of the type used for standard black and white cathode ray tubes in manufacture of faceplates for color picture tubes. Such soft glass may include those of leadbarium type glasses commercially available for use in the forming of black and white tube faces. Typically they have annealing points in the range of 430 C.-460 C., softening points in the order of 655 C., or less, and having a thermal coefficient of expansion in the range of 8S-100X10 C. While glass of this form is typically molded during its production with insufficient dimensional tolerance for suitable use in color tubes, such a panel may be recontoured and more closely dimensioned by oven treatment on a mold. Further-more, it has been found possible to install shadow mask supporting studs 12 interior of the panel flanges during the time that the panel is cooling from its recontouring process.

However, the recontouring and redimensioning, as well as the studing operation, carried out on such glass may introduce undesirable strains throughout the panel thereby rendering it dimensionally unstable in further handling and use. By bringing the panel 10 to a semi-fluid state in the annealing furnace 15, at a proper temperature for a sufiicient period of time and with proper buildup and run down with respect to that temperature, such strain can be relieved. Furnace 15, for example, may be as long as feet or longer and a conveyor device 17 is used to transport the panel 10 through this furnace. Since the panel 10 does have considerable size and weight, and since it will be in a semi-fluid state, and since the convey-or 17 is so long, the inevitable irregularities in the level of the conveyor throughout its length will cause undesired distortion or disturbance of the panel unless it is properly supported during the annealing process. Furthermore, the panel must be supported during annealing so that its own weight is evenly distributed and so that the area of support is not so small that it causes impressions in the softened glass surface contacted by the support means for the panel. As seen in FIGS. 2-4, the support device comprises a base frame 20 in the form of a ring having a diameter somewhat less than the smaller dimension of the panel 10'. A frame member or bar 22 is pivotally mounted to the ring 20 by means of a shoulder bolt and nut 23. The pivotal axis for the member 22. is horizontal with the device laid upon the conveyor 17. A stud 25 is secured to the member 22 outwardly of the pivot 23 and the stud extends through an enlarged aperture 26 in the side wall of the ring 20. This is to limit the pivotal movement of the frame member 22.

There are four support posts extending upwardly from the base frame assembly. Posts 30 and 31 are fixed to the base frame 20 opposite the pivot 23 and equidistant from this pivot. The support posts 32 and 33 are fixed at opposite ends of the frame member 22. The upper ends of the support posts 30-33 form a horizontal plane when the base assembly rests on a flat horizontal surface and these posts are preferably secured in a manner such that they are positioned at the corners of an imaginary rectangle.

The support posts 30-33 are tubular at the top and a paid 40 of stainless steel wool is carried in the upper end of each post. Panel 10 is then supported face down upon the pads 40. The support posts provide even or substantially even distribution of the weight of the rectanglar glass panel. The pivotal or rocking action of the bar or frame member 22 will maintain the pads in engagement with the panel despite limited relative shifting of the panel on the posts. The pads 40, of course, prevent impressions or indentations in the semi-soft glass.

It will be appreciated that the upstanding peripheral flanges of a faceplate panel 10 are relatively thick compared to the. viewing area of the faceplate panel; and hence, there is substantial weight to be supported by the annealing fixture which receives it and supports it during the annealing process. In addition, the viewing area of the faceplate panel defines a rather complex curve, and it is this portion which is engaged by the annealing fixture. Although it is desirable to center the faceplate panel on the annealing fixture, this is not always possible and deviations occur. With the present invention it will be seen that, within limits, upon disposing a faceplate panel on the fixture in an unbalanced condition such that the panel initially engages only one of the fixed posts 30, 31 or one of the movable posts 32, 33 and the other two posts, the weight of the panel will cause a pivoting of the bar 22 until the panel also engages the remaining posts. Thus, the weight of the faceplate panel is distributed on all four posts rather than any three as would be accomplished if the assembly frame were rigid.

I claim:

1. A device for supporting the glass faceplate panel of a cathode ray tube on a conveyor passing through an oven for annealing purposes, including in combination a ring-shaped base frame adapted to be placed on the conveyor, a frame member pivotally mounted to said base frame about a horizontal axis with said frame on the conveyor, first and second support posts secured to said base frame, third and fourth support posts secured to said frame member on opposite sides of the pivotal mounting thereof, said first through fourth support posts extending upwardly from said base frame and said frame member with said posts positioned at the corners of a rectangle with respect to one another and steel wool mounted on the tops of said support posts to cushion said base plate and to prevent indentations in the soft glass thereof.

2. A device for supporting a rectangular glass faceplate panel of a color cathode ray tube on a conveyor passing through an oven for annealing purposes, including in combination, a ring-shaped base frame adapted to be placed on the conveyor, a frame member pivotally mounted to said base frame about a horizontal axis with said base frame positioned on the conveyor, first and second support posts secured to said base frame on opposite sides of, and equidistant from, a point diametrically disposed from the pivot point of said member and said ring, third and fourth support posts secured to said frame member on opposite sides of, and equidistant from, the pivot point, said first through fourth support posts extending upwardly from said base frame and said frame member with said support posts positioned at the corners of a rectangle with respect to one another and steel wool mounted on the tops of said support posts to cushion said face plate and to prevent indentations in the soft glass thereof.

3. The device of claim 2 further comprising means for limiting the rotation of said frame member relative to the plane defined by said ring-shaped base frame.

4. The device of claim 3 wherein said limiting means is further defined by said ring-shaped base frame defining an aperture adjacent said pivotal connection with said frame member, and comprising a stud attached to said frame member and extending through said aperture on said ring-shaped base frame whereby said frame member will be limited in its rotation relative to the plane defined by said ring-shaped base frame when said stud engages said base frame.

References Cited UNITED STATES PATENTS 1,901,947 3/1933 Bescherer 248188.3 2,923,542 2/1960 Clank 269-296 3,117,392 1/1964 Jun-kunc 248l88.3 3,258,323 6/1966 Kirk 65l14 X OTHER REFERENCES German printed application L 12,570, October 1956 filed by Lindard.

ROBERT C. RIORDON, Primary Examiner. 

1. A DEVICE FOR SUPPORTING THE GLASS FACEPLATE PANEL OF A CATHODE RAY TUBE ON A CONVEYOR PASSING THROUGH AN OVEN FOR ANNEALING PURPOSES, INCLUDING IN COMBINATION A RING-SHAPED BASE FRAME ADAPTED TO BE PLACED ON THE CONVEYOR, A FRAME MEMBER PIVOTALLY MOUNTED TO SAID BASE FRAME ABOUT A HORIZONTAL AXIS WITH SAID FRAME ON THE CONVEYOR, FIRST AND SECOND SUPPORT POSTS SECURED TO SAID BASE FRAME, THIRD AND FOURTH SUPPORT POSTS SECURED TO SAID FRAME MEMBER ON OPPOSITE SIDES OF THE PIVOTAL MOUNTING THEREOF, SAID FIRST THROUGH FOURTH SUPPORT POSTS EXTENDING UPWARDLY FROM SAID BASE FRAME AND SAID FRAME MEMBER WITH SAID POSTS POSITIONED AT THE CORNERS OF A RECTANGLE WITH RESPECT TO ONE ANOTHER AND STEEL WOOL MOUNTED ON THE TOPS OF SAID SUPPORT POSTS TO CUSHION SAID BASE PLATE AND TO PREVENT INDENTATIONS IN THE SOFT GLASS THEREOF. 